I have a script which finds all the directories within a given directory and stores them in an array. In the original version of the script, I used something like this: 
my $dirname=cwd();
my $sys_get_dirs = "ls -l $dirname | egrep \'^d\'";
my @dirlist=`$sys_get_dirs`;

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I want to expand the script as a cross-platform script; both Linux and Windows. Is there a Perl function, command, structure - or something - I can employ in my script to somehow "detect" what OS it's running on? Is it something plainly obvious that I'm missing?

In reply to recognizing OS by PerlZealot

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